921UL oil burp

I hate to ask, but did you happen to forget to take the cap off the oil tank? I made that mistake early on. You’ll never hear it burp if you can’t hear it burp.

Also, I have had the 50+ turns issue because my oil settles into the sump after long periods and I added a little too much oil. If you have more oil than is necessary AND the settling sump issue, it can take MANY turns to bring it back up AND it may be so full the oil just kind of “blurbs” instead of burps. Check the level. If you’re 50 turns in and it’s at the top of the flat, you’re probably fine but may have added too much oil? Just a thought.

Check for a collapsed return line. If the crankcase is leaking it may not be building enough pressure to burp when properly rotating the propeller. If it’s a 2007 or older look for a cracked crankcase, can be difficult to see but an oily spot will grow when it’s running. I had one 914 that was cracked on top and undetectable until viewed while running when it was blowing out bubbles of oil.

I have turned the engine through 50 BLADES, not rotations. In addition to that, I have a 3 blade prop. 50 to sixty BLADES would be 16 to 20 revolutions.

 My original post was not clear.

Yes, I removed the cap on the oil tank and stood behind the prop to turn it so I would be sure to hear the burp. I have usually stood in front and pulled the prop through 3 or 4 revolutions to hear the burp.

I thank all of you for your comments. I get the impression that this does not necessarily indicate a problem. I worked on the electric flaps yesterday so I did not run the engine. The plan for tomorrow (Wed) is to balance the newly overhauled carbs and then do the compression test, so I will check this issue before and after running.

I checked the serial number and crankcase number several months ago and the engine was produced in 2017.